Abstract

Nanocrystalline zirconia thin films have been deposited at ambient temperature by dc magnetron sputtering on glass and quartz substrates. The crystallite size as calculated from the x-ray diffraction patterns in the films varies between 10 and and is dependent on oxygen percentage in the sputtering gas. Interestingly, the presence of monoclinic and cubic phase is observed for the filmsdeposited on glass at 40%, 60%, and 80% of oxygen in the sputtering gas, while those deposited on quartz showed only the monoclinic phase. Refractive index decreased with increase in percentage of oxygen in the sputter gas. Significantly, even at 100% oxygen in the sputtering gas, films of thickness of the order of have been grown starting from the metallic Zr target. The dielectric constants were measured using the extended cavity perturbation technique at -band frequency . The dielectric constant and loss tangent showed a very small decrease with increase in frequency but exhibited a stronger dependence on processing parameters. The dielectric constants of the films at microwave frequencies ranged between 12.16 and 22.3.

Received 28 June 2007Accepted 26 November 2007Published online 17 January 2008

Acknowledgments:

The authors acknowledge financial support from ISRO for the work. D.P. acknowledges a SRF from ISRO and K.S. acknowledges DLRL for a fellowship. Facilities provided by the UGC, UGC-SAP, DST-FIST, and UGC-UPE programs are gratefully acknowledged.